The research, by Susan M. Kaech, PhD, a postdoctoral fellow in microbiology and immunology at Emory University School of Medicine, and principal investigator Rafi Ahmed, PhD, director of the Emory Vaccine Center and a Georgia Research Eminent Scholar, was published online November 16 and will be printed in the December issue of Nature Immunology. Other members of the research team were E. John Wherry and Bogumila T. Konieczny of Emory University School of Medicine, and Joyce T. Tan and Charles D. Surh of The Scripps Research Institute.
During an acute viral infection, CD4 and CD8 T cells activated by specific viral antigens dramatically expand in number and become effector T cells. These cells kill the virus-infected cells and also produce cytokines. Most effector cells die within a few weeks, after their initial job is complete. Only about 5 to 10 percent survive to become long-term memory cells, which are capable of mounting a strong and rapid immune response when they come into contact with the original virus, even years later. Scientists have not clearly understood the mechanisms of memory cell production, and a major unanswered question has been how to distinguish the small fraction of cells likely to survive in long-term memory.
This team of investigators found that expression of the interleukin 7 (IL-7)
receptor, which binds the cytokine IL-7 and is required for T cell survival,
is increased in a small subset
Contact: Holly Korschun
Emory University Health Sciences Center